The DOJ has filed a brief in United States v Windsor, the case challenging the constitutionality of section three of the Defense of Marriage Act. The brief argues that section three of DOMA, which prohibits the federal government from recognizing same-sex marriages performed in states where they are legal, violates the Equal Protection Clause of the 14th Amendment:
“Section 3 of DOMA violates the fundamental constitutional guarantee of equal protection…
The law denies to tens of thousands of same-sex couples who are legally married under state law an array of important federal benefits that are available to legally married opposite-sex couples. Because this discrimination cannot be justified as substantially furthering any important governmental interest, Section 3 is unconstitutional.”
But there is one very important element of this brief. The DOJ is essentially banking on the Supreme Court deciding to apply a heightened standard of review in the case rather than the rational basis test, which is extremely deferential to legislative actions. The brief agrees with the 2nd Circuit Court of Appeals that heightened scrutiny should be applied and it lays out all of the familiar arguments for that conclusion. And in the end, the brief explicitly admits that the law would only be constitutional under heightened review:
The government does not challenge the constitutionality of DOMA Section 3 under deferential rational basis review, but Section 3 would fail a more searching form of that review.
I think this is a mistake. In the two previous rulings of great importance for gay rights, Lawrence v Texas and Romer v Evans, both authored by Justice Kennedy, the court struck down the laws being challenged even under rational basis review. Kennedy is pretty strong on gay rights, but he seems reluctant to declare that this is a suspect class and therefore subject to heightened or strict scrutiny. So it seems unwise to give up the argument that this law is unconstitutional even by the most lax standard the court can apply. You can read the full brief here.